First and foremost, my thoughts and prayers go out to all you in or near Boston or that are effected by this terrible tragedy.
I will never understand why people do **** like this... There is no financial gain, nor victory in such mindless killing.
If I had to guess, this seems like the work of amateurs because the blasts were not too large and the explosions/blast radios shot out to the side and went upward which suggest that the perpetrator didn't position the bomb properly or did not have access to more sophisticated explosive techniques. Moreover, the perpetrator(s) didn't detonate the bombs at the time when it would have caused the most devastation. This suggests that the bombing was not properly coordinated or that the killer may have had second thoughts before detonating.
Thank god the bomb was detonated hours after the majority of runners had crossed the finish line. It was estimated that only 5000 runners were left on the track when it was detonated. My guess is that the perp experienced some emotional conflict before setting the bomb off or was targeting a certain group of people who he thought would be in that area near the end of the race.
Ultimately, the most likely explanation is that the people responsible are an amateur domestic cell or single individual that didn't have access to sophisticated explosives, second guessed his actions and then when he finally got the courage to carry out this sick act, set off the bombs.
Let's hope we catch whoever is responsible soon and that people in Boston can rest assured that they are safe from anymore attacks.
